Conventional diesel engines include, in the exhaust passage, a diesel particulate filter (DPF), which captures particulate matter (PM) contained in exhaust gas. In such a DPF, in order to maintain the function of capturing particulate matter, a regeneration process, in which particulate matter captured by the DPF is burnt, is performed.
For example, Patent Document 1 discloses a filter regeneration device, in which a burner is arranged upstream of a DPF. Exhaust gas at the temperature raised by the burner is sent to the DPF to perform a regeneration process for the DPF. In the burner, fuel for the engine and air for combustion are introduced to a combustion area, which is a tubular inner space of a flame stabilizer, to produce mixture of the fuel and the air for combustion. The air-fuel mixture is then burnt by ignition to raise the temperature of the exhaust gas.